I've taken the opportunity provided by GundamInfo's YouTube channel to re-watch Zeta Gundam, for free, legally. They haven't uploaded the whole series yet, but as of this post they're at Episode 25 (half-way, exactly). So far, it's kept me watching.
I've enjoyed this series so far, and a large part of that is the returning characters from the original series demonstrating the effects of the One Year War (the events of the original series) had on them and how they dealt with those effects. Maybe you need to have some years on you to appreciate that, but it's been vital for me to see this in action.
The contrast with the newer, often younger, characters who have yet to undergo those trials and be initiated into maturity accordingly shows in practical performance. Many of these characters are pilots, so their ability to control their emotions directly affects them in combat; the ones who can't are the ones that get killed in action.
The plot also moves. Not quite the blistering pace of the Pulps, but still quite fast, and yet entirely believable because what happens logically and emotionally follows from one beat to the next. But the best thing? By this point, the folks funding the franchise know damn well what the audience wants--mecha action--and this series gives it to you on the regular. That can lead to a lazy production with no character development, but they managed to get it in there, get it right, and allow them to have moments outside of the mobile suits that are no less meaningful.
You can see how this sense of storytelling became institutionalized by comparing this series from the 1980s to more recent releases like Gundam Unicorn or Iron-Blooded Orphans (also available at the aforementioned channel). I think that it's here, with Zeta, that many of the tropes now iconic with Gundam shows in particular (and Real Robot shows generally) got nailed down- something that influenced many shows, games, etc. going forward. I can't wait to watch the remaining 25 episodes again. This series still delivers.
Which brings me to an aside.
R. Talsorian's Mekton series of tabletop RPGs really are "Gundam: The RPG", with the capacity to emulate other shows a welcome side-benefit. This is most obvious with the final version, Mekton Zeta, its mandatory supplement (the one with the full construction system), and its one full campaign setting (Starblade Batallion, which echoes Zeta and Double Zeta a lot). If you're going for a mecha RPG, Mekton Zeta is your go-to option. It's not a pozzed game, so that's another good thing about it. I have a post on it here.